Van Horn Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Van Horn. A median date has an even chance of a later freeze in spring, or an earlier one in fall.
The last spring freeze typically comes around March 21 and the first fall freeze around November 11, a growing season of about 234 days.
- Median at 36°F
- last April 6, first November 1
- Median at 32°F
- last March 21, first November 11
- Median at 28°F
- last March 4, first November 21
Last freeze in spring
The chance of a later freeze than the date shown. At 10 percent, one spring in ten still freezes after the date; planting after the 10 percent date for 32°F is the cautious choice.
| Threshold | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 24 | Apr 17 | Apr 13 | Apr 8 | Apr 6 | Apr 3 | Mar 31 | Mar 25 | Mar 18 |
| 32°F | Apr 9 | Apr 3 | Mar 31 | Mar 25 | Mar 21 | Mar 15 | Mar 11 | Mar 7 | Mar 2 |
| 28°F | Mar 23 | Mar 16 | Mar 11 | Mar 7 | Mar 4 | Mar 1 | Feb 26 | Feb 21 | Feb 14 |
| 24°F | Mar 9 | Mar 2 | Feb 27 | Feb 23 | Feb 17 | Feb 13 | Feb 8 | Feb 3 | Jan 25 |
| 20°F | Feb 25 | Feb 17 | Feb 10 | Feb 4 | Jan 30 | Jan 23 | Jan 15 | Jan 6 | Dec 26 |
| 16°F | Feb 14 | Feb 4 | Jan 28 | Jan 21 | Jan 12 | Jan 5 | Dec 31 | Dec 24 | Dec 14 |
First freeze in fall
The chance of an earlier freeze than the date shown. At 10 percent, one fall in ten freezes before the date.
| Threshold | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 18 | Oct 23 | Oct 27 | Oct 29 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 14 |
| 32°F | Oct 27 | Oct 31 | Nov 4 | Nov 7 | Nov 11 | Nov 14 | Nov 16 | Nov 20 | Nov 24 |
| 28°F | Nov 4 | Nov 11 | Nov 15 | Nov 18 | Nov 21 | Nov 24 | Nov 27 | Dec 1 | Dec 4 |
| 24°F | Nov 15 | Nov 22 | Nov 25 | Nov 29 | Dec 2 | Dec 5 | Dec 8 | Dec 13 | Dec 19 |
| 20°F | Nov 26 | Dec 3 | Dec 8 | Dec 13 | Dec 18 | Dec 23 | Dec 28 | Jan 3 | Jan 13 |
| 16°F | Dec 6 | Dec 13 | Dec 21 | Dec 26 | Dec 31 | Jan 4 | Jan 11 | Jan 24 | Feb 2 |
Growing season length
Days between the last spring and first fall freeze at each threshold, with the chance of a season at least that long.
| Threshold | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | 230 | 223 | 217 | 212 | 208 | 204 | 200 | 194 | 186 |
| 32°F | 256 | 250 | 243 | 239 | 234 | 229 | 223 | 218 | 208 |
| 28°F | 285 | 276 | 270 | 265 | 260 | 255 | 251 | 245 | 236 |
| 24°F | 314 | 305 | 298 | 292 | 287 | 281 | 276 | 268 | 259 |
| 20°F | 356 | 345 | 337 | 331 | 323 | 316 | 309 | 301 | 288 |
| 16°F | 365 | 365 | 365 | 365 | 363 | 356 | 346 | 338 | 324 |
How often it gets that cold
The share of years with at least one night at or below each temperature.
- 36°F or colder
- 100% of years
- 32°F or colder
- 100% of years
- 28°F or colder
- 100% of years
- 24°F or colder
- 100% of years
- 20°F or colder
- 95% of years
- 16°F or colder
- 56% of years
Degree days
A degree day is one degree of the daily mean temperature beyond a base, for one day. Heating degree days count cold (the fuel a house burns), cooling degree days heat, growing degree days the warmth a crop needs; each crop has its own base.
- Heating degree days, base 65°F
- 2,584
- Cooling degree days, base 65°F
- 2,040
- Growing degree days, base 40°F
- 8,694
- Growing degree days, base 45°F
- 7,041
- Growing degree days, base 50°F
- 5,530
- Growing degree days, base 55°F
- 4,194
- Growing degree days, base 60°F
- 3,031
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 634 | 0 | 25 |
| February | 448 | 0 | 74 |
| March | 285 | 9 | 224 |
| April | 107 | 58 | 406 |
| May | 22 | 237 | 681 |
| June | 0 | 464 | 913 |
| July | 0 | 484 | 949 |
| August | 0 | 450 | 914 |
| September | 11 | 258 | 698 |
| October | 100 | 76 | 450 |
| November | 358 | 4 | 159 |
| December | 618 | 0 | 37 |
What this means
NOAA computes these from the daily lows at the station over 1991-2020, fitting the dates of each year's last and first freeze to a distribution, so a date can be stated at any level of risk. 36°F is a frost risk for tender plants on a clear, calm night, since the ground cools below the air above it; 32°F is a freeze; 28°F is a hard freeze that kills most annuals.
The station is 0.6 km from Van Horn. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.
More
Sources
NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00419295 (Van Horn). Public domain.